A State-of-the-Art Survey on Real-Time Issues in Embedded Systems Virtualization

Abstract

Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a comprehensive survey on real-time issues in virtualization for embedded systems, covering popular virtualization systems including KVM, Xen, L4 and others

Security Challenges of Virtualization Hypervisors in Virtualized Hardware Environment

“…[39]. Some other security benefits of virtualization are: • The centralized storage used in virtual machine environments prevents loss of data when a device is either • Virtual Machine provides flexibility.…”

“…This is achieved by the infrastructure provider using virtualization, where customers of the cloud service share the same physical services that are virtualized logically. Hypervisor can be run in two ways: It can run directly on the hardware this is called the (Type-1 or the bare-metal virtualization) or it can run on top of a host machine operating system this is known as the (Typw-2 or hosted virtualization) [1]. The native or bare-metal hypervisor is more robust, efficient and delivers greater scalability more than a hosted hypervisor, this is because the bare-metal hypervisor has direct access to the hardware resource of the host machine rather being on top of the host machine operating system.…”

Evaluating the Performance and Behaviour of RT-XEN

“…A VMM can run either on the hardware directly (called bare-metal, or Type-1 virtualization), or on top of a host operating system (called hosted, or Type-2 virtualization) [2].…”

“…In recent years, it has been deployed in embedded systems domain such as avionics systems and industrial automation where a strong emphasis on real-time performance is required [2]. Also, it has been used for soft real-time applications such as media-based ones which demonstrate inadequate performance due to the impede of virtualization components such as low performance virtualization I/O and increased scheduling latency.…”

“…In its current state, Xen does not support hosting real-time operating systems which require low VM scheduling latency to meet real-time task's deadline. [3] Recently, efforts were undertaken by researchers [2] to enhance the real-time capabilities of the Xen platform in order to be deployed in a variety of use cases.…”